|Family XLIII. PROCELLARINAE. FULMARS.
GENUS V. THALASSIDROMA, Vigors. PETREL.
LEAST PETREL.--MOTHER CAREY'S CHICKEN.
|Genus||THALASSIDROMA PELAGICA, Linn.
In August 1830, being becalmed on the banks of Newfoundland, I obtained
several individuals of this species from a flock composed chiefly of
Thalassidroma Leachii, and Th. Wilsoni. Their smaller size, and the more rapid
motions of their wings, rendered them quite conspicuous, and suggested the idea
of their being a new species, although a closer inspection shewed them to belong
to the present. In their general manners, while feeding, floating on the water,
or rambling round the boat in which I went in pursuit of them, they did not
differ materially from the other species. Their flight, however, was more
hurried and irregular, and none of them uttered any note or cry, even when
wounded and captured. I have been assured that this bird breeds on the sandy
beaches of Sable Island on the coast of Nova Scotia; but not having had an
opportunity of visiting it, or any other breeding place, I here present you with
Mr. HEWITSON's observations on this subject.
"In an excursion," says this amiable and enterprising naturalist, "through the Shetland Islands during the present summer, in search of rarities for this work, (the British Oology,) I had the very great satisfaction of seeing and taking many of these most interesting birds alive; they breed in great numbers on several of the islands, principally upon Foula, the north of Hunst, and upon Papa, and, Oxna, two small islands in the Bay of Scalloway; the last of these I visited on the 31st of May in hopes of procuring their eggs (it being the season in which most of the sea-birds begin to lay); but in this; I was disappointed; the fishermen, who knew them well by the name of Swallows, assured me that my search would be quite useless, that they had not yet "come up from sea," and so it proved. Sixteen days after this (June 16th and three following days) I was at Foula, but was alike unsuccessful, the birds had arrived at their breeding places, but had not yet begun laying their eggs; numbers of them were sitting in their holes, and were easily caught: one man brought me about a dozen tied up in an old stocking, two of which I kept alive in my room for nearly three days, and derived very great pleasure from their company; during the day they were mostly inactive, and after pacing about the floor for a short time, poking their head into every hole, they hid themselves between the feet of the table and the wall; I could not prevail upon them to eat any thing, though I tried to tempt them with fish and oil; their manner of walking is very light and pleasing, and differing from that of every other bird which I have seen; they carry their body so far forward and so nearly horizontal, as to give them the appearance of being out of equilibrium. In the evening, toward sun-set, they left their hiding places, and for hours afterwards, never ceased in their endeavours to regain their liberty; flying round and round the room, or fluttering against the windows; when flying, their length of wing, and white above the tail, gives them a good deal the appearance of our House-Martin. I went so bed and watched them in their noiseless flight, long ere I fell asleep, but in the morning they had disappeared; one had fortunately make its escape through a broken pane in the window which a towel should have occupied, the other had fallen into a basin, full of the yolks of eggs which I had been blowing, and was drowned. I regretted much the fate of a being so interesting, by its very remarkable, wandering, solitary, and harmless life. Before leaving Shetland I again visited the island of Oxna, and though so late as the 30th of June, they were only just beginning to lay their eggs. In Foula they breed in the holes in the cliff, at a great height above the sea; but here under stones which form the beach, at a depth of three or four feet, or more, according to that of the stones; as they go down to the earth, beneath them, on which to lay their eggs. In walking over the surface, I could hear them, very distinctly, singing in a sort of warbling chatter, a good deal like Swallows when fluttering above our chimneys, but harsher; and in this way, by listening attentively, was guided to their retreat, and, after throwing out stones as large as I could lift on all sides of me, seldom failed in capturing two or three seated on their nests, either under the lowest stone or between two of them. The nests, though of much the same materials as the ground on which they were placed, seem to have been made with care; they were of small bits of stalks of plants, and pieces of hard dry earth. Like the rest of the genus, the Stormy Petrel lays invariably one egg only. During the day-time they remain within their holes; and though the fishermen are constantly passing over their heads, (the beach under which they breed being appropriated for the drying of fish,) they are then seldom heard, but toward night become extremely querulous; and when most other birds are gone to rest, issue forth in great numbers, spreading themselves far over the surface of the sea. The fishermen then meet them very numerously; and though they have not previously seen one, are sure to be surrounded by them upon throwing pieces of fish overboard."
The egg measures one inch and an eighth in length, six and a half eighths in breadth, is nearly equally rounded at both ends, rather thick-shelled, and pure white, but generally with numerous minute dots of dull red at the larger end, sometimes forming a circular band.
STORMY PETREL, Thalassidroma pelagica, Nutt. Man., vol. ii. p. 327.
LEAST PETREL, Thalassidroma pelagica, Aud. Orn. Biog., vol. iv. p. 310.
Male, 5 3/4, 13 1/2.
Not uncommon on the Banks of Newfoundland. Not observed to breed on the American coast.
Bill shorter than the head, slender, compressed towards the end, straight, with the tips curved. Upper mandible with the nostrils forming a tube at the base, beyond which, for a short space, the dorsal line is nearly straight, then suddenly decurved, the sides declinate, the edges sharp, the tip compressed and acute. Lower mandible with the angle rather long, narrow, and pointed, the dorsal line beyond it very slightly concave and decurved, the sides erect, the edges sharp, the tip slightly decurved.
Head of moderate size, roundish, anteriorly narrowed. Neck short. Body rather slender. Feet of moderate length; very slender; tibia bare at its lower part; tarsus very slender, reticulate; hind toe extremely minute,. being reduced, as it were, to a slightly decurved claw; anterior toes rather long and extremely slender, obscurely scutellate above, connected by striated webs with concave margins. Claws slender, arched, compressed, acute.
Plumage very soft, blended, the feathers distinct only on the wings, which are very long and narrow; primary quills tapering, but rounded, the second longest, the first three and a half twelfths, the third a twelfth and a half shorter; secondaries short, the outer incurved, obliquely rounded. Tail rather long, broad, slightly rounded, of twelve broad rounded feathers.
Bill and feet black. Iris dark brown. The general colour of the upper parts is greyish-black, with a tinge of brown and moderately glossed; the lower parts of a sooty-brown; the secondary coverts margined externally with dull greyish-white; the feathers of the rump and the upper tail-coverts white, with the shafts black, the tail-coverts broadly tipped with black.
Length to end of tail 5 3/4 inches, to end of claws 5 1/4, to end of wings 6 1/4; extent of wings 13 1/2; wing from flexure 5 1/8; tail 2 1/8; bill above (4 1/2)/8, along the edge of lower mandible 5/8; tarsus 7/8; middle toe and claw 7/8; outer toe nearly equal; inner toe and claw (5 1/2)/8. Weight 4 1/2 drachms; the individual poor.
The female resembles the male.
A male bird, from Nova Scotia, examined. The upper mandible internally has a longitudinal median ridge; the palate is convex, with two lateral ridges. The tongue is 5 1/2 twelfths long, emarginate and serrulate at the base, very much flattened, tapering to a horny point. The heart, Fig. 1, [a], is of a very elongated narrow conical form, 2 twelfths in length, 4 twelfths in breadth at the base. The lobes of the liver, [b c], are equal, 6 1/2 twelfths long. The oesophagus, [d e], is 1 inch 10 twelfths long, of a uniform diameter of 2 1/2 twelfths; behind the liver, it enters as it were a large sac, [f g h], 9 twelfths of an inch long, which gradually expands to a diameter of 6 twelfths, forming a broad rounded fundus [g], then curves forwards on the right side, and at [h] terminates in a small gizzard, about 3 twelfths long, and nearly of the same breadth, from the left side of which comes off the intestine. The latter passes forward, curving to the right, behind and in contact with the posterior surfaces of the liver, then forms the duodenal fold, [h j k], in the usual manner. The intestine, on arriving at the right lobe of the liver, at [k], receives the binary duct, curves backward beneath the kidneys, and forms several convolutions, which terminate above the proventriculus. It then becomes much narrower, and passes directly backward, in a straight course to the rectum, which is only 4 twelfths of an inch long. The coeca are oblong, 1 1/4 twelfths in length, and 1/2 twelfth in diameter. The intestine is 81/2 inches long, its diameter diminishing gradually from 2 twelfths to 3/4 of a twelfth.
In Fig. 2 are represented the lower part of the oesophagus, [d e f]; the proventricular sac, [f g h]; the very small gizzard, [h]; the duodenal fold of the intestine, [i j k]. Here the parts are viewed from the left side.
Fig. 3 represents:--the proventricular sac thrust forward, [f g h]; the gizzard, [h]; the duodenum, [i j k], pulled to the right side; the convolutions of the intestine, [l m], under the kidneys; the coeca, [n]; the rectum, [o]; and the cloaca, [p].
The proventricular glands are very numerous, but not so closely placed as is usual, although scattered over a much larger extent, from [e] to [g], in Fig. 2. Between the termination of the glands and the stomach there is a portion destitute of glandules. The stomach or gizzard has its muscular coat thick, its tendons moderate, its inner surface covered with a rather thick but not very hard epithelium, which is more prolonged on two opposite sides, although in the fundus it is complete.
This curious digestive apparatus agrees very nearly with that described and figured by Sir EVERARD HOME as that of Alca Alle. The stomach, it is seen, is excessively large in proportion to the size of the bird; but why it should be so, and moreover be curved in this manner, is not very obvious. Conjectures are easily made, and might run in this form. This little bird, which wanders over the face of the ocean, subsisting upon garbage, oily and fatty substances, small fishes, and even sea-weeds, requires a large stomach for the reception of its heterogeneous fare, which not being always very nutritious or easily digestible, must be very plentifully intermixed with the gastric juices, and detained a considerable time; which conditions are accordingly provided for by the very great number and extensive dispersion of the proventricular glandules, and the curve of the organ. Should any hard substances, as crustacea, be introduced, they are pounded by the gizzard; but as the bird is little addicted to feeding on such substances, that organ is reduced to a very small size.
The aperture of the glottis is 1 1/2 twelfths long. The trachea is 1 inch 7 twelfths in length, wide, flattened, its diameter from 2 twelfths to 1 1/2 twelfths; its rings unossified, 82 in number. The bronchi are short, wide, of about 12 half rings.